The proposed study will extend an ongoing investigation of 136 families to assess associations between martial conflict and children's adjustment prospectively and longitudinally as children move from middle childhood through adolescence. Data will be collected at two times, first when siblings are 13 and 15-years-old, and second, two years later, when they are 15 and 17 years old. The first aim is to bring a new and exciting perspective to the study of marital relationships by investigating how marital conflict is linked to adolescents' adjustment and relationships differently for two siblings growing up in the same family. The second aim is to assess, for one of the first times, links between parents' marital relationships and adolescents' romantic relationships. Links between parents' marriages and adolescents' relationships with siblings, friends, and peers will also be investigated. The third aim is to further elucidate the processes that connect marital conflict to adolescents' adjustment and relationships. Recent theoretical and empirical work has suggested three mechanisms that may link the marital relationship to children's psychological adjustment and ability to sustain healthy relationships with romantic partners, siblings, friends, and peers. These mechanisms are children's cognitive appraisals of parents' marital conflict, children's and parents' emotional regulation and expression, and characteristics of parent-child relationships. In the proposed study, each of these processes will be tested: In addition, adolescents' individual characteristics such as temperament and gender will be investigated as moderators between the parental marital relationship and adolescents' adjustment and relationships. Observing marital and family interaction, interviewing adolescents, and collecting adolescents', parents', and teachers' questionnaire responses will collect data.